Colored composites exhibiting long afterglow characteristics and colored articles exhibiting long afterglow characteristics

ABSTRACT

Disclosed are a composite exhibiting long afterglow characteristics comprising at least a phosphorescence layer and a coloration layer, wherein the phosphorescence layer contains a phosphor and binder and the coloration layer contains a colorant, phosphor and binder, and an article exhibiting long afterglow characteristics which has the composite exhibiting long afterglow characteristics on at least a part of the surface thereof.

TECHNICAL FIELD

The present invention relates to composites exhibiting long afterglowcharacteristics, which can be in various colors and exhibit highphosphorescence luminance even if they are in a deep color such as red,green and black or in metallic color, and articles comprising thecomposites.

BACKGROUND ART

There have been known pigments that can emit phosphorescence visible ina dark place for relatively long time (afterglow) after irradiated bysunlight or light from artificial lighting and repeatedly show suchcharacteristics. These pigments absorb light energy in a light place andemit phosphorescence in a dark place like charge and discharge ofstorage battery, and called as phosphorescent pigments. There have alsobeen known luminous pigments that comprise a phosphorescent pigment anda radioactive substance such as tritium, ¹⁴⁷ Pm and ²²⁶ Ra, whereradioactive ray emitted by the radioactive substance stimulates thephosphorescent pigment to emit phosphorescence.

Such phosphorescent pigments and luminous pigments are currently usedfor various products utilizing their long afterglow characteristics, forexample, switches, lights for carrying, articles for use in darkroom,handrails, luminous indications such as wall indications, guidancesigns, escape tools, other phosphorescent indications such asphosphorescent safety marks, ornamental articles such as ash trays,earrings and tablecloths, printed matter, toys, stationery and the like.For example, as uses of the phosphorescent pigments, Japanese PatentUnexamined Publication No. Hei 4-51405 (JP-A-51405/92) disclosesphosphorescent wall panels for escape corridor, Japanese PatentUnexamined Publication No. Hei 1-111075 (JP-A-111075/89) disclosesphosphorescent fibers, Japanese Patent Unexamined Publication No. Hei1-200388 (JP-A- 200388/89) discloses light emitting ropes, and JapanesePatent Unexamined Publication No. Hei 1-200389 (JP-A-200389/89)discloses phosphorescent sheets for indications.

Such products as mentioned above may be desired to be colored dependingon their uses while maintaining the long afterglow characteristics.

However, when the conventional phosphorescent pigments are colored,their phosphorescence luminance is substantially reduced depending oncolor and color strength. For example, according to JIS K 5120,Commentary of Phosphorescent Pigments, Commentary p.5, "Commentary List:Drop of Phosphorescence Luminance of Phosphorescent Pigments byColoration", the phosphorescence luminance of such pigments is reducedto, considering the luminance when not colored as 100%, 15.7% whencolored in green (added amount: 3.6%), 14.1% when colored in reddishorange (added amount: 2.4%) or 5.1% when colored in red (added amount:9.1%). Thus, reddish orange or red coloration reduces thephosphorescence luminance more significantly.

To solve the above problem, for example, Japanese Patent UnexaminedPublication No. Hei 3-166269 (JP-A-166269/91) discloses coloredphosphorescent pigments and luminous pigments comprising organicpigments. However, phosphorescence luminance of these coloredphosphorescent pigments and luminous pigments is still quite low becausetheir phosphorescence luminance is not enhanced, and their colorvariation has substantial limitation.

Nevertheless, as products and commercial needs are more diversified,articles exhibiting long afterglow characteristics with highphosphorescence luminance and being colored in various colors have beenhighly desired.

For example, articles exhibiting afterglow characteristics in metalliccolor such as gold and silver or in black have not been practically usedyet, because phosphorescence cannot be obtained by a combination ofphosphorescent pigment and metallic color pigment or black pigment. Thisis because a layer containing a metallic color pigment or black pigmentexhibits poor light transmission and hence a phosphorescent pigmentcontained therein cannot store light energy.

By the way, phosphorescent phosphors exhibiting higher phosphorescenceluminance compared to conventional phosphorescent pigments have beendeveloped (Japanese Patent Unexamined Publication No. Hei 7-11250(JP-A-11250/95)). However, these phosphorescent phosphors themselvesstill cannot solve the above problem. The reduction of phosphorescencecaused by mixing with a colored pigment is still too high tosubstantially enable coloration in metallic color such as gold andsilver or in black.

The present invention has been completed to solve these problems, and anobject of the present invention is to provide a composite exhibitinglong afterglow characteristics which can exhibit higher phosphorescenceluminance and color tone comparable to conventional ones with respect tothe colors conventionally used for coloration of such materials such asred and green, and an article utilizing such a composite exhibiting longafterglow characteristics.

Another object of the present invention is to provide a compositeexhibiting long afterglow characteristics which is in a colorconventionally impossible to be used for the coloration of suchmaterials, for example, metallic color such as gold and silver, black orthe like, and can exhibit sufficient phosphorescence luminance, and anarticle utilizing such a composite exhibiting long afterglowcharacteristics.

DESCRIPTION OF THE INVENTION

The present invention provides a composite exhibiting long afterglowcharacteristics comprising at least a phosphorescence layer and acoloration layer, wherein the phosphorescence layer contains a phosphorand binder and the coloration layer contains a colorant, phosphor andbinder.

The present invention provides an article exhibiting long afterglowcharacteristics a part or all of which surface is composed of the abovecomposite exhibiting long afterglow characteristics.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a sectional illustration of a colored composite exhibitinglong afterglow characteristics according to the present invention.

FIG. 2 is a sectional illustration of a colored composite exhibitinglong afterglow characteristics according to the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

The composite exhibiting long afterglow characteristics of the presentinvention is essentially characterized in that it comprises thephosphorescence layer and the coloration layer as independent layers.The phosphorescence layer is a layer containing phosphor and binder, andthe coloration layer is a layer containing colorant, phosphor andbinder.

Conventional products exhibiting long afterglow characteristics arecomposed only of a coloration layer containing a colorant and phosphor.In contrast, the composite exhibiting long afterglow characteristics ofthe present invention comprises the phosphorescence layer and thecoloration layer mentioned above, and this characteristic enables higherphosphorescence luminance with comparable color tone, or coloration in acolor which cannot have been compromised with the long afterglowcharacteristics while maintaining the long afterglow characteristics.

The phosphorescence layer is a layer containing a phosphor and binder.

The "phosphor" used in the present invention is a substance emittingphosphorescence, and any substance may be used so long as it has such aproperty. For example, phosphorescent pigments and luminous pigmentsfall within the meaning of "phosphor". The phosphorescent phosphorsdisclosed in Japanese Patent Unexamined Publication No. Hei 7-11250(JP-A-11250/95) also fall within the meaning of the "phosphor" of thepresent invention.

While copper activated zinc sulfide (ZnS:Cu) is generally used as the"phosphor", other materials containing inorganic fluorescent pigments ororganic fluorescent pigments and exhibiting long afterglowcharacteristics can also be selected. For example, zinc silicatephosphors, zinc sulfide cadmium phosphors, calcium sulfide phosphors,strontium sulfide phosphors, calcium tungstate phosphors and the likecan be used. In particular, phosphorescent pigments containing strontiumaluminate as base crystals and rare earth element as activator arepreferred, because they exhibit high phosphorescence luminance.

On the other hand, the luminous pigment consists of a phosphorescentpigment which is added with a radioactive material so that the pigmentshould have spontaneous light-emitting property. For example, itconsists of copper-activated zinc sulfide added with a radioactivematerial such as tritium and promethium 147 ("Pigment Handbook, RevisedNew Edition", pp.506-512, published Mar. 10, 1989, Seibundo ShinkoshaCo., Ltd., edited by Japan Pigment Technology Association).

The "binder" used for the present invention may be any binder materialso long as it can form a layer together with the phosphor. For example,it may be a resin-based material. The binder preferably has goodtransparency so that high phosphorescence luminance can be obtained.Examples of resins constituting the binder are, but not limited to,acrylic resins, alkyd resins, epoxy resins, urethane resins, acrylicsilicone resins, silicone resins, fluorocarbon resins, melamine resinsand the like.

Ratio of the phosphor and the binder and thickness of thephosphorescence layer may be suitably selected depending onphosphorescence luminance required for an objective composite exhibitinglong afterglow characteristics. As the content of the phosphor in thephosphorescence layer increases, or as the thickness of thephosphorescence layer increases, phosphorescence luminance generallytends to become higher. However, when the content of the phosphorbecomes too high, it may become difficult to form the phosphorescencelayer or strength of the layer may be reduced. From such points of view,the content of the phosphor in the phosphorescence layer is suitably 50%by weight or more, preferably 70-95% by weight, more preferably 80-90%by weight. The thickness of the phosphorescence layer is in the rangeof, for example, 10-500 μm, practically in the range of 50-200 μm. Twoor more phosphorescence layers may be used in order to obtain thephosphorescence layer of a large thickness.

The coloration layer is a layer containing a colorant, phosphor andbinder.

The "phosphor" and the "binder" may be selected from those explained forthe phosphorescence layer hereinabove.

As the colorant, those used for ordinary inks or paints can be used asthey are. For example, they can be an inorganic or organic dye orpigment. Their color is not particularly limited.

In particular, according to the present invention, composites exhibitinglong afterglow characteristics in metallic color or black can also beprovided.

As a metallic color pigment, while ordinary metal powder and bronzepowder may be used, deposited metal pigments in metallic color havingscalelike particle shape are preferred, because they can afford highphosphorescence luminance. The deposited metal pigments are in the formof powdery flakes obtained by depositing metal (e.g., brass for goldencolor and aluminum for silver color) on a plastic piece or the like(polyethylene terephthalate film, aluminum etc.) and triturating theplastic piece or the like. The deposited metal is protected by atransparent (yellow) resin layer after the deposition. As a commerciallyavailable product, for example, ELGEE R Gold #325 (Oike Industry Co.,Ltd) can be mentioned.

As a black pigment, while carbon black or the like can be used,deposited black pigments having scalelike particle shape are preferred,because they can afford high phosphorescence luminance. The depositedblack pigments can be obtained in the same manner as in the preparationof the deposited metal pigments using black material instead of metal.As a commercially available product, for example, ELGEE R Black #325(Oike Industry Co., Ltd) can be mentioned.

The above deposited metal pigments and the deposited black pigments arein the form of powdery flakes, and therefore they have an averagediameter larger than that of usual pigments. Accordingly, by using thedeposited metal pigments and the deposited black pigments, good lighttransmission in the coloration layer can be advantageously realized.

Content of the colorant and thickness of the coloration layer may besuitably selected depending on the desired color of the compositeexhibiting long afterglow characteristics of the present invention.However, it should be taken into consideration that, as the content ofthe colorant and thickness of the coloration layer increase,phosphorescence luminance of the composite exhibiting long afterglowcharacteristics tends to be lowered.

The phosphor contained in the coloration layer affects phosphorescenceluminance of the composite exhibiting long afterglow characteristicstogether with phosphorescence of the phosphorescence layer. Inparticular, in order to obtain high phosphorescence luminance, it ispreferred that a single particle of the phosphor or a plurality ofcontiguous particles thereof are present over the whole thickness of thecoloration layer. For example, by using, for the coloration layer,phosphor particles at least a part of which have a diameter larger thanthe thickness of the coloration layer, or phosphor particles having anaverage diameter larger than the thickness of the coloration layer, asingle particle of the phosphor can be present over the whole thicknessof the coloration layer. In order that a plurality of contiguousparticles the phosphor should be present over the whole thickness of thecoloration layer, it is necessary to use a content of the phosphor inthe coloration layer higher than a certain level. For example, when thecontent of the phosphor in the coloration layer is 70-95% by weight,preferably 80-95% by weight, a plurality of contiguous particles of thephosphor can be present over the whole thickness of the colorationlayer.

The above mentioned configurations of the particles of the phosphor willbe further explained with reference to the appended FIGS. 1 and 2.

Both of FIGS. 1 and 2 represent a cross-sectional view of the coloredcomposite exhibiting long afterglow characteristics of the presentinvention, which comprises a substrate 1 on which the phosphorescencelayer 2 and the coloration layer 3 are provided in this order. Thephosphorescence layer 2 comprises the binder 4 and the phosphor 5. Thecoloration layer 3 comprises the binder 4, the phosphor 5 and thecolorant 6 (deposited metal pigment in metallic color).

In FIG. 1, a plurality (2 or 3) of contiguous particles of phosphor 5are together present over the whole thickness of the coloration layer 3.Each particle of the phosphor 5 is in contact with the adjacentparticle. In FIG. 2, a single particle of phosphor 5 is a present overthe whole thickness of the coloration layer 3. When the particles are insuch configurations, light from the coloration layer 3 side (upper sideof the Figure) easily transmits through the coloration layer 3 to thephosphorescence layer 2, and hence accumulation of light energy in thephosphor 5 in the phosphorescence layer 2 can be enhanced. In addition,phosphorescence emitted from the phosphorescence layer 2 easilytransmits through the coloration layer 3 to the surface of thecoloration layer 3, and hence the phosphorescence intensity becomeshigher. Moreover, accumulation of light energy in the phosphor 5 of thecoloration layer 3 and discharge thereof can also be promoted.

Because of the presence of the particles of phosphor 5 in the colorationlayer 3, the deposited metal pigment 6 can be dispersed with properspacing and hence it does not prevent transmission of the light to thephosphorescence layer 2 (excitation light) and the light from thephosphorescence layer 2 (phosphorescence).

While the coloration layer of the composite exhibiting long afterglowcharacteristics of the present invention can have only a single color,it may contain two or more portions with different colors so that somefigures, patterns, characters, marks or the like can be formed.

The composite exhibiting long afterglow characteristics of the presentinvention may have an additional layer on at least a part of the surfaceof the phosphorescence layer and/or the coloration layer. Such anadditional layer may be a substrate layer, and such a substrate layermay be substantially transparent or opaque with respect to visible lightor it may be white.

The substrate layer may have a printing layer on at least one surfacethereof. When the substrate layer is white or has a white printinglayer, phosphorescence luminance can be improved. The substrate layermay be a sheet, film, card or the like composed of paper, plastics,cloth, glass, metal, ceramic, leather or the like.

The above additional layer may also be a protective layer. Theprotective layer is preferably substantially transparent as to visiblelight.

The present invention also provides an article exhibiting long afterglowcharacteristics which comprises the above composite exhibiting longafterglow characteristics on at least a part of its surface.

Kind of the article is not particularly limited. For example, it may bea switch, light for carrying, article for use in darkroom, handrail,luminous indication such as wall indication, guidance sign, escape tool,other phosphorescent indication such as phosphorescent safety mark,ornamental article such as ash tray, earring and tablecloth, printedmatter, toy, stationery and the like.

When the article is one having a reversed image like decalcomania paper,the order of superimposition of the phosphorescence layer 2 and thecoloration layer 3 is reversed.

Materials to be printed with such decalcomania paper may be variousarticles such as ceramic, cloth, plastics, metal, glass, enamel,building materials and the like.

Methods for preparing the composite exhibiting long afterglowcharacteristics and the article exhibiting long afterglowcharacteristics of the present invention will be explained hereinafter.

The composite exhibiting long afterglow characteristics of the presentinvention can be prepared by forming the phosphorescence layer and thecoloration layer successively on a suitable substrate by a methodcommonly used for the preparation of coated membranes or films, forexample, printing, coating or the like.

For example, the phosphorescence layer can be formed from an inkcomposed of a mixture containing a phosphor and medium containingbinder. The coloration layer can be formed from an ink composed of amixture containing colorant, phosphor and medium containing binder, oran ink composed of a mixture containing an ink containing colorant,phosphor and medium containing binder. The composition of the ink may besuitably decided considering the composition of intended layer,viscosity of the ink and the like. As the medium containing binder, acommercially available single-part or two-part type medium exhibitinggood contact for various materials and good weather resistance can besuitably used. As an example of medium particularly suitable for clothand exhibiting particularly excellent transparency, KDBDL (trade name),Matsui Coloring Matter Chemical Co., Ltd., can be mentioned.

An ink for forming the phosphorescence layer can be prepared by, forexample, mixing 100 parts by weight of medium with 100-400 parts byweight, preferably 150-300 parts by weight of phosphor. An ink forforming the coloration layer can be prepared by, for example, mixing 100parts by weight of medium with 100-400 parts by weight, preferably150-300 parts by weight of phosphor and 1-15% by weight of inkcontaining coloring pigment.

In order to from a relatively thick layer to obtain high phosphorescenceluminance, the layer is preferably formed by screen printing or thelike. Depending on the shape of materials to be printed, flatbed screenprinting, curved surface printing and roll-feed printing as well aselectrostatic printing can be performed. ("Basic Printing Technology",pp.114-118, published Jan. 30, 1993, Sangyo Tosho Co., Ltd., edited byTakahiro Tsunoda et al.).

Mesh of screen used for the screen printing is not particularly limited,and it may be suitably decided considering diameters of coloring pigmentand phosphor, viscosity of ink and the like. For example, a layer havinga film thickness of about 10 μm to 100 μm can be formed by screenprinting using screen fabric of 80 mesh to 200 mesh.

When the composite exhibiting long afterglow characteristics comprisesno substrate (i.e., it comprises only the phosphorescence layer and thecoloration layer), it can be obtained by forming the phosphorescencelayer and the coloration layer on a suitable substrate and then peelingthe formed composite exhibiting long afterglow characteristics from thesubstrate. When the composite exhibiting long afterglow characteristicsof the present invention contains a substrate, phosphorescence layer andcoloration layer, it can be obtained by forming the phosphorescencelayer and the coloration layer successively on a suitable substrate.

The composite exhibiting long afterglow characteristics of the presentinvention may have a protective layer. Such a protective layer may be,for example, a UV curing resin layer. However, the protective layer isnot limited to this. The composite exhibiting long afterglowcharacteristics of the present invention can have an adhesive layer.

The present invention will be further explained with reference to thefollowing examples.

EXAMPLE 1

Ink for forming phosphorescence layer (1)

200 g of phosphorescent pigment (N Yako, phosphorescent pigmentcomprising strontium aluminate as base crystals and rare earth elementsas activator, average diameter of 20 μm, Nemoto & Co., Ltd.) and 100 gof medium (Vinyl Screen Printing INK ATC 780N, solid content: 30% byweight, Seiko Advance Co., Ltd.) were mixed by sufficiently stirringthem to afford Ink for forming phosphorescence layer (1).

Ink for Forming Coloration Layer (1)

160 g of phosphorescent pigment (N Yako, phosphorescent pigmentcomprising strontium aluminate as base crystals and rare earth elementsas activator, average diameter of 20 μm, Nemoto & Co., Ltd.), 80 g ofmedium (Vinyl Screen Printing INK ATC 780N, solid content: 30% byweight, Seiko Advance Co., Ltd.) and coloration ink (Vinyl ScreenPrinting INK Red: ATC Weather-resistant 538 Process Red, solid content:53.3% by weight, Seiko Advance Co., Ltd.) were mixed by sufficientlystirring them to afford Ink for forming coloration layer (1).

Preparation of Composite Exhibiting Long Afterglow Characteristics

The above Ink for forming phosphorescence layer (1) was screen printedon Yupo (thickness: 247 μm, Oji-Yuka Synthetic Paper Co., Ltd.) usingprinting fabric of T100 mesh to afford a phosphorescence layer having asize of 92×56 mm and thickness of 90 μm.

Subsequently, the above Ink for forming coloration layer (1) was screenprinted on the above phosphorescence layer using printing fabric of T100mesh to afford a coloration layer having a thickness of 82 μm.

Phosphorescence luminance of the resulting composite exhibiting longafterglow characteristics of the present invention was measured oneminute after extinction.

Measurement of Luminance

A sample of composite whose energy had been sufficiently discharged in adark place was irradiated by light from a 27 w fluorescent lampcorresponding to brightness of about 5400 lx for ten minutes. One minuteafter the completion of the light irradiation for light energyaccumulation, phosphorescence intensity (afterglow) of the sample wasmeasured using luminance photometer (LS-100, Minolta Co., Ltd.).Phosphorescence efficiency was calculated as intensity ofphosphorescence (mcd) per unit amount (1 g) of the phosphorescentpigment contained in the composite exhibiting long afterglowcharacteristics.

Measurement of Color Tone

Color of the sample was visibly compared with DIC color reference andthe closest DIC color reference number was determined. The results areshown in Table 1.

Comparative Example 1

Ink for forming coloration layer (1) prepared in Example 1 was screenprinted on Yupo identical to that of Example 1 using printing fabric ofT100 mesh (printed twice) to afford a coloration layer having athickness of 157 μm.

Phosphorescence luminance one minute after extinction and color of theresulting printed matter were measured as in Example 1. The results areshown in Table 1.

                  TABLE 1                                                         ______________________________________                                                  Example 1  Comparative Example 1                                    ______________________________________                                        Phosphorescence                                                                           Phosphorescent                                                      layer pigment:                                                                 86 wt %                                                                       Binder: 14 wt%                                                                Thickness: 90 μm                                                          Coloration layer Phosphorescent Phosphorescent                                 pigment: pigment:                                                             86.07 wt % 86.07 wt %                                                         Binder: 13.59 wt % Binder: 13.59 wt %                                         Coloring pigment Coloring pigment                                             0.34 wt % 0.34 wt %                                                           Thickness: 82 μm Thickness: 157 μm                                     Luminance of 349 243                                                          afterglow                                                                     (mcd/m.sup.2)                                                                 Phosphorescence 1.52 1.25                                                     efficiency (mcd/g)                                                            Color tone                                                                    Hue Red Red                                                                   DIC #274 #274                                                               ______________________________________                                    

From the results shown in Table 1, it can be seen that the compositeexhibiting long afterglow characteristics of the present inventionexhibits higher afterglow luminance with the same color tone compared tothe sample comprising only the coloration layer. It can also seen thatit exhibits higher phosphorescence efficiency, i.e., the phosphor isutilized more efficiently for the emission of phosphorescence.

EXAMPLES 2-6

A phosphorescence layer having a thickness 90 μm was formed in the samemanner as in Example 1. Subsequently, inks for forming coloration layerwith various ratios of the phosphorescent pigment and the medium orratios of the coloration ink and the medium were each screen printed onthe phosphorescence layer in the same manner as in Example 1 to affordcoloration layers (red).

Phosphorescence luminance one minute after extinction and color of theresulting composites exhibiting long afterglow characteristics of thepresent invention were measured as in Example 1. The results are shownin Table 2.

                  TABLE 2                                                         ______________________________________                                        Coloration layer                                                                    Phos-                                                                      phore-  Colora-  Lumi-                                                        scent  tion  nance of                                                         pig-  pig- Thick- after-                                                     Exam- ment Binder ment ness glow Color tone                                 ple   (wt %)  (wt %)  (wt %)                                                                              (μm)                                                                             (mcd/m.sup.2)                                                                        Hue  DIC                             ______________________________________                                        2     88.5    11.23   0.28  81    390    Red  #275                              3 90.20  9.56 0.24 109  394 Red #261                                          4 86.36 13.43 0.21 84 497 Red #261                                            5 86.39 13.41 0.21 57 533 Red #261                                            6 86.19 13.53 0.28 53 438 Red #275                                          ______________________________________                                    

EXAMPLE 8

A phosphorescence layer having a thickness of 179 μm was formed as inExample 1 by applying the ink twice, and then a coloration layer wasformed as in Example 1.

The resulting composite exhibiting long afterglow characteristics of thepresent invention exhibited luminance one minute after extinction of 596mcd/m² and phosphorescence efficiency of 2.26 mcd/g, and, regardingcolor tone, it exhibited red hue corresponding to DIC #275.

Comparative Example 2 and 3

Ink for forming coloration layer (1) was applied once or three times asin Comparative Example 1 to afford a coloration layer of having athickness of 90 μm or 220 μm.

Luminance one minute after extinction, phosphorescence efficiency andcolor tone of the resulting composites exhibiting long afterglowcharacteristics are shown in Table 3.

                  TABLE 3                                                         ______________________________________                                                     Comparative                                                                           Comparative                                                Example 2 Example 3                                                         ______________________________________                                        Luminance of   208       235                                                    afterglow                                                                     (mcd/m.sup.2)                                                                 Phosphorescence 2.49 0.79                                                     efficiency                                                                    (mcd/g)                                                                       Color tone                                                                    Hue Red Red                                                                   DIC #261 #295                                                               ______________________________________                                    

EXAMPLES 9-11

A phosphorescence layer having a thickness 90 μm was formed in the samemanner as Example 1. Subsequently, inks for forming coloration layercontaining the following inks as coloration ink (content of colorationink was 3% for Examples 9 and 10 and 10% for Example 11) were screenprinted on the phosphorescence layer in the same manner as in Example 1to form coloration layers.

Luminance one minute after extinction, phosphorescence efficiency andcolor tone of the resulting composites exhibiting long afterglowcharacteristics of the present invention are shown in Table 4.

Example 9 (blue): Coloration ink (Vinyl Screen Printing INK Blue: ATCWeather-resistant 546 Process Blue, solid content: 47.7% by weight,Seiko Advance Co., Ltd.)

Example 10 (green): Coloration ink (Vinyl Screen Printing INK Green: ATC304 Process Green, solid content: 53.4% by weight, Seiko Advance Co.,Ltd.)

Example 11 (gold): ELGEE R Gold #325, Oike Kogyo Co., Ltd.

                  TABLE 4                                                         ______________________________________                                                  Example 9                                                                              Example 10                                                                              Example 11                                       ______________________________________                                        Luminance of                                                                              941        1305      405                                            afterglow                                                                     (mcd/m.sup.2)                                                                 Phosphorescence 4.54 6.13 2.01                                                Efficiency                                                                    (mcd/g)                                                                       Color tone                                                                    Hue Blue Green Gold                                                           DIC #99 #64 #620                                                            ______________________________________                                    

EXAMPLE 12

A protective layer having a thickness of 65 μm was formed using an inkfor forming UV curing protective layer (Vinyl Screen Printing INK UV8414Clear, Seiko Advance Co., Ltd.) on the coloration layer of the compositeexhibiting long afterglow characteristics of the present inventionobtained in Example 1.

Luminance one minute after extinction of the obtained compositeexhibiting long afterglow characteristics of the present invention was356 mcd/m², and, regarding color tone, it exhibited red huecorresponding to DIC #274.

EXAMPLE 13

Ink for Forming Phosphorescence Layer (2)

230 g of phosphorescent pigment (GSS, average diameter: 21 μm, Nemoto &Co., Ltd.), 100 g of medium (Vinyl Screen Printing INK VIC 800, SeikoAdvance Co., Ltd.) and 20 g of cellosolve acetate were mixed bysufficiently stirring them to afford Ink for forming phosphorescencelayer (2).

Ink for Forming Coloration Layer (2)

230 g of phosphorescent pigment (GSS, average diameter: 21 μm, Nemoto &Co., Ltd.), 100 g of medium (Vinyl Screen Printing INK VIC 800, SeikoAdvance Co., Ltd.) and 3 g of coloration ink (Vinyl Screen Printing INKGreen: ATC 304 Process Green, solid content: 53.4% by weight, SeikoAdvance Co., Ltd.) were mixed by sufficiently stirring them to affordInk for forming coloration layer (2).

Preparation of Composite Exhibiting Long Afterglow Characteristics

The above Ink for forming phosphorescence layer (2) was screen printedon Yupo (thickness: 247 μm, Oji-Yuka Synthetic Paper Co., Ltd.) usingprinting fabric of T100 mesh to afford a phosphorescence layer having asize of 92×56 mm. Subsequently, the above Ink for forming colorationlayer (2) was screen printed on the above phosphorescence layer usingprinting fabric of T100 mesh to afford a coloration layer. Thephosphorescence layer and the coloration layer had a total thickness of101 μm.

Phosphorescence luminance one minute after extinction of the resultingcomposite exhibiting long afterglow characteristics of the presentinvention was 129 mcd/m².

Comparative Examples 4-6

Fluorescent printed layers were formed by coater printing usingcommercially available fluorescent pigment or fluorescent inks, andtheir phosphorescence luminance one minute after extinction (mcd/m²) wasmeasured. The results are shown in Table 5.

The inks used are shown below.

Comparative Example 4: Ink formed by mixing 10 g of luminous pigment(Kurachi Co., Ltd.) and 10 g of medium (Vinyl Screen Printing INK ATC780N, solid content: 30% by weight, Seiko Advance Co., Ltd.)

Comparative Example 5: Color Luminous Paint Pink (Shinleuch Co., Ltd.)

Comparative Example 6: Color Luminous Paint Green (Shinleuch Co., Ltd.)

                  TABLE 5                                                         ______________________________________                                                       Comparative                                                                             Comparative                                                                             Comparative                                  Example 13 Example 4 Example 5 Example 6                                    ______________________________________                                        Luminance of                                                                           129       32        47      60                                         afterglow                                                                     (mcd/m.sup.2)                                                                 Color torn Green Pale Fluorescent Fluorescent                                   orange red green                                                          ______________________________________                                    

From the results shown in Table 5, it can be seen that the compositeexhibiting long afterglow characteristics of the present inventionexhibit higher afterglow luminance compared to the commerciallyavailable fluorescent paints even when GSS, conventional phosphor, wasused.

I claim:
 1. A composite exhibiting afterglow characteristics comprisingat least a phosphorescence layer and a coloration layer, wherein thephosphorescence layer contains a phosphor and binder and the colorationlayer contains a colorant, phosphor and binder.
 2. The compositeexhibiting afterglow characteristics of claim 1, wherein a singleparticle of the phosphor or a plurality of contiguous particles thereofcontained in the coloration layer are present over the whole thicknessof the coloration layer.
 3. The composite exhibiting afterglowcharacteristics of claim 2, wherein at least a part of phosphorparticles contained in the coloration layer have a diameter larger thanthe thickness of the coloration layer.
 4. The composite exhibitingafterglow characteristics of claim 2, wherein the phosphor particlescontained in the coloration layer have an average diameter larger thanthe thickness of the coloration layer.
 5. The composite exhibitingafterglow characteristics of claim 1, wherein content of the phosphor inthe coloration layer is 55-95% by weight.
 6. The composite exhibitingafterglow characteristics of claim 1, wherein the colorant contained inthe coloration layer is colored pigment.
 7. The composite exhibitingafterglow characteristics of claim 6, wherein the colored pigment ismetallic color pigment or black pigment.
 8. The composite exhibitingafterglow characteristics of claim 7, wherein the metallic color pigmentor the black pigment is in the form of scales.
 9. The compositeexhibiting afterglow characteristics of claim 1, wherein the phosphorcontained in the phosphorescence layer is a phosphorescent pigmentand/or luminous pigment.
 10. the composite exhibiting afterglowcharacteristics of of claim 1, wherein the phosphor contained in thecoloration layer is a phosphorescent pigment and/or luminous pigment.11. The composite exhibiting afterglow characteristics of claim 1,wherein the binders contained in the phosphorescence layer and thecoloration layer are substantially transparent with respect to visiblelight.
 12. The composite exhibiting afterglow characteristics of claim1, wherein the coloration layer comprises two or more portions indifferent colors.
 13. The composite exhibiting afterglow characteristicsof claim 1, wherein an additional layer is provided on at least a partof surface of at least one of the phosphorescence layer and thecoloration layer.
 14. The composite exhibiting afterglow characteristicsof claim 13, wherein the additional layer is a substrate layer.
 15. Thecomposite exhibiting afterglow characteristics of claim 14, wherein thesubstrate layer is substantially transparent or opaque with respect tovisible light or in white.
 16. The composite exhibiting afterglowcharacteristics of claim 14, wherein the substrate has a printing layeron at least one surface thereof.
 17. The composite exhibiting afterglowcharacteristics of claim 13, wherein the additional layer is aprotective layer.
 18. The composite exhibiting afterglow characteristicsof claim 17, wherein the protective layer is substantially transparentwith respect to visible light.
 19. The composite exhibiting afterglowcharacteristics of claim 13, wherein the additional layer is an adhesivelayer.
 20. An article exhibiting afterglow characteristics which has thecomposite exhibiting afterglow characteristics of claim 1 on at least apart of the surface thereof.
 21. The article exhibiting afterglowcharacteristics of claim 20, which is a luminous indication, guidancesign, escape tool, phosphorescent indication, ornamental article,printed matter, toy or stationery.